1. Technical Field
The present invention relates to a plasma display panel, and more particularly, to a plasma display panel having a structure capable of reducing noise by reducing a gap between a dielectric layer and barrier ribs.
2. Related Art
The plasma display panel recently replaced the cathode ray tube (CRT), and is a device for displaying images, in which a discharge gas is inserted between two substrates having a plurality of electrodes, a discharge voltage is applied to the panel to generate ultraviolet rays, and a phosphor layer of a predetermined pattern is excited by the ultraviolet rays so as to display an image.
The plasma display panel can be classified into a direct current (DC) type and an alternating current (AC) type. In the DC type plasma display panel, electrodes are exposed in a discharge space, and therefore electric charge moves directly between corresponding electrodes. In the AC type plasma display panel, electrodes of at least one side are covered by a dielectric layer, and thus a discharge is performed by movement of wall charge accumulated on the dielectric layer.
Since the charge directly moves between the corresponding electrodes in the DC type plasma display panel, the electrodes are severely damaged. Thus, an AC type plasma display panel having a three-electrode surface discharge type structure has been recently adopted.
In general, the AC plasma display panel includes an upper substrate displaying images, and a lower substrate facing the upper substrate, the two substrates being in parallel with each other. Sustain electrode pairs are formed on a lower surface of the upper substrate, and the sustain electrode pairs are embedded in an upper dielectric layer. In addition, address electrodes are formed on an upper surface of the lower substrate so as to cross the sustain electrode pairs, and the address electrodes are embedded in a lower dielectric layer. Barrier ribs defining discharge cells are formed between the lower dielectric layer and the upper dielectric layer. A discharge gas is inserted into the discharge cells, and red, green and blue color phosphor layers are selectively formed in the discharge cells for realizing colors.
In the plasma display panel described above, the barrier ribs are fabricated in predetermined patterns, and after that, they are baked. Then, after performing the latter processes, end portions of the barrier ribs become higher than center portions thereof due to extraction generated as a result of some components of the barrier ribs coming out during the processes. When the end portions of the barrier ribs become higher, detachment between the center portion of the barrier rib and the upper dielectric layer occurs. The detachment causes vibration noise during driving of the panel. Especially, the detachment becomes worse if terminal units of electrodes are drawn to edges of the substrates through the barrier ribs, the end portion of which become higher, in a state where the thickness of the dielectric layer is not uniform since the dielectric layer covers the electrodes.